We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations.
Always consult with the appropriate authorities if you have questions concerning what is permissable in your locale.

The UNID 1 PPS signal remained active til at least 2018-04-11 22:30UTC when I last checked.

Some observations,

The UNID 1 PPS signal remained on 7285kHz from the time CaptKliegle reported it at 2018-04-11 11:13UTC until I last checked at 22:30UTC

At 2018-04-11 20:00UTC China Radio International started broadcasting on 7285kHz but the UNID 1 PPS pip could still be heard, at least at my location. I did not note when China Radio International stopped broadcasting and I am not sure where the transmitter for this broadcast was located - maybe Cerrik Albania ?

Having had a bit of time to poke around, I started to check about for the PIP or ditter than Token has reported. I noted quite a lot of interesting activity.

Firstly, above and below 7285kHz I noticed PIP's every 3 seconds (approximately), one was 35kHz above at 7320kHz and the other 85kHz below at 7200kHz. further searching found PIPs every 120kHz at (6960kHz - not sure but I thought I could hear this one), 6900kHz but nothing lower in frequency; 7440khz, 7560kHz, 7680kHz, 7800kHz, 7920kHz, 8040kHz, 8160kHz, 8280kHz, 8400kHz, 8520kHz, and 9300kHz . All with an apparent repetition rate of once every 3 seconds (approx) except 9300kHz which appeared to be every 6 to 7 seconds I measured pulse width from a simple recording using audacity at 128ms which is interestingly 8x the pulse width of the UNID 1 PPS signal on 7285kHz (16ms pulse width).

Time wise, this was all between approximately 2018-04-11 16:00UTC and 17:00UTC

Also noted where PIPs on 7880kHz, 7640kHz, 7620kHz, 7400kHz, and 7300kHz all with an apparent repetition rate of once every 6 to 7 seconds (approx)

Furthermore, I noted another set spaced 110kHz apart at 7460kHz, 7570kHz, 7680kHz, all with an apparent repetition rate of once every 3 seconds (approx) and another on 7920kHz also every 3 seconds.

All of these nice and neatly spaced and repetitive PIPs has me wondering whether or not these were real signals and not just some artifact of my SDR receiver (airspy HF+) and computer BUT most were quite weak and others a bit stronger and all exhibited fading as would a signal which was propagated rather than locally created. Still, this is something to consider with respect to these other PIPs I was hearing and seeing on the SDR waterfall. Was I chasing my tail or where these PIPs real signals?

I did not note any double PIPs but occasionally one may have been dropped or just not heard as a result of fading.

Whether these PIPs were related to the UNID 1 PPS on 7285kHz is uncertain.

Whether these PIPs were related to the PIP or Ditter signals that Token has reported is uncertain other than being of a similar pattern and repetition rate.

When I have measured the PIP pulse width I get approximately 16ms and it has a quick leading and trailing edge plus whatever it is seems to be running a lot of power all contributing to it's apparent bandwidth. I can often here the PIP even when tuned off frequency 10kHz.

Still no idea on who or what. Maybe related to some HARRP or SUPER DARN or Aricebo research activity. I have been poking around the FCC licence database (and the Canadian one too) but so far have not stumbled across any likely candidates but then again maybe I did but couldn't see the connection.

This does not appear to be related to the PIP's that Token often mentions (but it may be). I have seen them both active at the same time and I have seen each active while the other was not. Also the UNID 1 PPS PIP seems to stay within the amateur 40m and 30m bands whereas the other PIPs do not.

I was on 40m CW last night using my HW-8 (DC receiver, wide as a barn door). I could hear the Pips from 10kc away. Really loud here. Heard them around 7095, 7105 & 7115. Had to shut down due to an approaching t-storm. I'll have to hook up the 40m coaxial loop & see if I can get some kind of bearing. 100% analog here so I have to find them first then chase 'em when they move.

1718 UTC - Checking out the 20 meter amateur band when I just noticed the PIP on 14265 kHz, signal is sS9 +20dB in WNY. One second intervals between signal pulses.1723 UTC - Just moved to 14260 kHz.1724 UTC - PIP is gone.

Did anyone else notice this transmission? It was on and offseveral times this evening. I hit the SDR record at 2358. The sigwas S9+20 here. It reminded me of a kind of screwed up WWVsound but there was never any announcements. At 000200 UTCthe sound changed and then it was off at 000500 UTC and Ihaven't heard anymore this evening but I do think I've heard iton other days. Best sound seemed to be in AM mode...

Thanks, ChrisI'm glad it wasn't just some local crud. Since a pic is worth 1K words,here's a screenshot for Justin Case (anyone is curious). The shot is just asthe sound changed at 000200 UTC. With the volume turned up, I could hearwhat sounded, to me, like 1 second time ticks.

I heard something similar ~a week ago but I was on the phone soI just clicked mute. As I recall... I was looking at the 20 meter digitalarea around 14100 kHz or so. The sig was gone by the time I got off the phone.73, Paul

0316 UTC - PIP has been pulsing every second since 0312 UTC on 6370. Signal S9 in WNY.0329 UTC - PIP still going, signal drops to S7 at times.0341 UTC - PIP still going, checked Web SDR's in N.E. Pa, Texas, Wash. D.C, and N. Utah and all are picking up the signal from S7 to S9. 0408 UTC - PIP still going.0420 UTC - PIP still going.